Importance is increasingly being placed on reduced emissions in harbors throughout the world. This also applies to ship movement. Nowadays, it is normal practice for ships to produce their electricity requirement in harbor using their own electricity producing equipment, generally one or more diesel generator or generators. Since these machines were optimized to burn heavy diesel oil, that is to say HFO, and in some cases also burn marine diesel oil, that is to say NDO, in harbor, these diesel generators produce amounts of soot, NOx, CO2 and SOx which should not be underestimated.
In order to prevent such, soot, NOx, CO2 and SOx formation, EU Guidelines 1999/32/EG and 93/12/EG have discussed ships in harbor being supplied with external energy. In this context, it is already known for ships to be supplied with electricity from the quay installation (frequently also referred to as “Cold Ironing”).
By way of example, U.S. Pat. No. 7,122,913 B2 discloses a modular harbor electricity supply for ships in harbor, which supply can be moved along the quay.
One problem with an electricity supply from the quay such as this is that it is necessary for the electricity supply to a ship in harbor to compensate for differences in the water level and the load level of the ship in harbor. Furthermore, the readiness of such a harbor power supply to operate from the quay may be adversely affected, for example at high tide.